Last year, 25 billion digital photos were saved to PC hard drives around the world. So says Lyra Research, a Massachusetts firm that keeps tabs on the digital-photography market. The company also claims that the total number of photos stored on our PCs has now reached 60 billion.

Many PC users organize their digital photos in directories all over their hard drives and use Windows Explorer to find them, but as a photo collection grows, this quickly becomes cumbersome. Using filenames to locate Word documents and MP3 files is one thing. Using them to locate photographs with such clever names as DCP_0013.JPG is quite another. When you're searching through a large stash of photos, you need more intuitive, more visual, ways to locate images.

Recognizing digital photography's growing popularity, Microsoft built some basic image management features into Windows XP. But its features still are not powerful enough for today's digital-camera users. Without the ability to organize pictures by dates, keywords, and metatags, such as subject and place, our images quickly disappear into a hard drive abyss. Meanwhile, storing and finding images are only part of the equation. People also need tools to touch up images and share them with others.

Image managers such as ACDSee, CompuPic, and Ulead Photo Explorer have been around for years. The earliest products on the market often looked a lot like Windows Explorer, with a list of directories down the left and thumbnails on the right.

It wasn't until Apple introduced iPhoto that image management caught the attention of mainstream computer users. Since iPhoto's release, a variety of companies have developed similar applications, mainly focusing on the Windows platform. We tested eight sub-$50 Windows-based image managers that go beyond Windows XP's capabilities.

The most exciting progress is seen in the innovative interfaces that offer an intuitive way to browse through all the images on your PC. Adobe Photoshop Album (which was still in private beta when we put this story to bed), Picasa, and Preclick Photo Organizer all offer a time line view that lets you scroll through your collection of photos chronologically, no matter where they're stored. This is a much better method than the outdated technique of moving from folder to folder. In fact, we predict that all image managers will eventually move to this paradigm.

If your picture taking has gone digital, you'll soon find yourself drowning in an ocean of photos that Microsoft won't be able to help you escape. Fortunately, with one of these programs, managing your image collection will be smooth sailing.